I have even heard the official say 2 out loud then waive it off. Going back to accurate on your counting, the two should come after the arms has went out, that way if you hit the verbal 2 it is good.

I also like the verbal part of it, I am not sure it is required, but in close tilts or scrambles sometimes as soon as they hear the 1 they get moving.

But yes consistancy is the key.